package 力扣日常刷题.木22一月.第10天0118;

/**
 * @author 帅小伙
 * @date 2022/1/18
 * @description dp[i][j] 表示 从i到j最长回文子序列
 */
public class Demo17动态规划中等最长回文子序列 {

    public int longestPalindromeSubseq(String s) {

        int n = s.length();
        int[][] dp = new int[n][n];

        for (int i = n - 1; i >= 0; i--) {
            dp[i][i] = 1;
            char c1 = s.charAt(i);
            for (int j = i + 1; j < n; j++) {
                char c2 = s.charAt(j);
                if (c1 == c2) {
                    dp[i][j] = dp[i + 1][j - 1] + 2;
                } else {
                    dp[i][j] = Math.max(dp[i + 1][j], dp[i][j - 1]);
                }
            }
        }
        return dp[0][n - 1];

    }


}
